Alkanes produced from carbohydrates could provide a renewable source of transportation fuel to complement the rapidly growing production of bio-diesel from vegetable oils and animal fats. UW-Madison researchers have developed a practical and energy-efficient catalytic process for producing high-quality long-chain liquid fuels from carbohydrates. The multi-stage process uses combinations of self- and crossed-aldol condensation reactions dehydration reactions and hydrogenation reactions to yield alkane alkene and ether products. Preferably this process starts with an acid-catalyzed dehydration of biomass-derived carbohydrates. Then an aqueous-phase aldol condensation reaction yields large organic compounds which are converted into long-chain alkanes via dehydration and/or hydrogenation. The aldol condensation reaction takes place in the presence of a stable recyclable and solid-base catalyst which is comprised of magnesium zirconium oxygen and possibly palladium. Applications: 1) Biofuel production 2) Production of useful feedstocks for making organic chemicals
1) Alkanes can be used as sulfur-free fuel components 2) Aldol condensation reactions occur in the aqueous phase enabling the generation of alkanes from renewable resources 3) Unlike the conversion of glucose to ethanol this reaction does not require an energy-intensive distillation step—alkanes spontaneously separate from the aqueous solvent 4) Environmentally friendly 5) Catalyst maintains significant activity after recycling and is potentially useful in other aqueous-phase catalyzed reactions 6) Reactions are appropriate for many types of reactors including batch semi-batch and continuous flow reactors